Hie Team,
I needed to convert a 12 VDC to -65 VDC, 2A using Webench Power Designer. It gave me a schematic based on an LM5116 converter. However, when I try to simulate using TINA-TI, the simulation runs into a convergence issue.
here is the schematic and the simulation file:
Here is the alert generated by Webench Power Designer
Here is the simulation file:
How best can I go around this?
Hello Nyasha
The device model works when the PGND and AGND pins are connected to the ground symbol.
The simulation works if you 1) connect the CIN ground to the positive connection of the COUT, 2) remove the ground symbol from the positive connection of the COUT, and 3) connect the negative connection of the COUT to the ground symbol.
-EL
Thank you @EricLee for your response, it was really helpful. I ran the simulation for 1s, however, the results I obtained were different from the Webench calculations. The simulation gave -11V instead of -65V calculated by Webench. I understand your workaround is different than the one designed by Webench. So, how can I tune this circuit to obtain the desired voltage level?
Hello Nyasha
I think your schematic is different than the WEBENCH recommendations. Please double check the component values.
--EL
